All practice pages/Interatomic theory/Elements

46Pd106.42

Element 46, a transition metal

Palladium

A precious metal that soaks up hundreds of times its own volume of hydrogen, and the catalyst inside most gasoline car exhausts.

At a glance

Symbol
Pd
Atomic number
46
Average atomic mass
106.42
Group
10
Period
5
Family
transition metal
Electron configuration
[Kr] 4d¹⁰
Electronegativity
2.20
Common ions
Pd²⁺ in most compounds

On the table

Periodic table with Palladium highlighted123456789101112131415161718123456757-7189-103HHeLiBeBCNOFNeNaMgAlSiPSClArKCaScTiVCrMnFeCoNiCuZnGaGeAsSeBrKrRbSrYZrNbMoTcRuRhPdAgCdInSnSbTeIXeCsBaLaCePrNdPmSmEuGdTbDyHoErTmYbLuHfTaWReOsIrPtAuHgTlPbBiPoAtRnFrRaAcThPaUNpPuAmCmBkCfEsFmMdNoLrRfDbSgBhHsMtDsRgCnNhFlMcLvTsOg

Period 5, group 10. The other transition metals are tinted, and every cell opens its own article.

Electrons and bonding

Like other transition metals, palladium loses its outer s electrons, and often some d electrons as well, to form positive ions, and it can form more than one kind.

Properties

State at 25 °C
solid
What it looks like
soft, silvery-white metal
Melting point
1554.9 °C
Boiling point
2963 °C
Density
12.0 g/cm³

Where it is found

Mined with platinum and nickel, mostly at Norilsk in Russia and in South Africa.

Discovery and name

William Hyde Wollaston isolated it from platinum ore in 1802 and, before announcing it, offered it anonymously for sale in a London shop in 1803 as new silver, which led other chemists to suspect a fraud. He named it after the asteroid Pallas, discovered in 1802.

What it is used for

Most goes into catalytic converters, especially for gasoline cars. It also goes into electronics, dental alloys, white gold jewelry and membranes that purify hydrogen. Palladium catalysts join carbon atoms together when making medicines, work recognized by the 2010 Nobel Prize in Chemistry.

In compounds

PdCl₂palladium(II) chloridePd(CH₃COO)₂palladium acetate, a catalystPdHₓpalladium hydride